Study On Antibacterial, Antivirus And Degradation Of Organic Pollutants With Nanometer Titanium Dioxide

The photocatalysis characteristic of nano-TiO2 which prepared by metastable-state chlorination was studied.Through the bacterial killing rate and the HbsAg destroyed test, studied the antibacterial effect and antivirus activity of TiO2 and explore its possible mechanism. Using the nature light irradiation, at the concentration of 1% TiO2 nanometer powder, the killing rate of Staphylococcus aureus, Escherichia coli and Bacillus subtilis var. niger was 97.7%, 99.7%, 88.2% respectively within 24 hours. HbsAg could be changed from positive to negative with the effect of 1% concentration of TiO2 within 12 hours. Furthermore, at the condition of different temperature, pH, and light source, the TiO2 had distinct antibacterial and antivirus activity. The ESR study indicated that the TiO2 powder could produce OH·under the dark condition which contribute to its antibacterial property. Photocatalytic degradation of phenol, 2,4-dicholorophenol and methyl orange by nano-TiO2 was studied under different conditions. The effect of organism concentration, catalyst amount, reaction time, temperature, the initial solution pH and light sources on the degradation rate was investigated. At the condition as followed: under high-pressure mercury lamp, 2% nano-TiO2, initial organism concentration of 2.5μg/ml, the removal rate of phenol and 2,4-dicholorophenol was 90.5% and 96.7% respectively. The research indicated that the nano-TiO2 exhibited high photocatalytic action under high pressure mercury lamp. It also showed some photocatalytic effect under nature light source and in the dark. The ESR study indicated that the TiO2 powder could produce OH·under the dark condition which contribute to its degradation of organism. The nano-TiO2 did not adsorb phenol but adsorb 2,4-dicholorophenol and methyl orange. The nano-TiO2 could be reusable by activation which helped it to become a widely used green environmental photocatalyst. Three different immobilized method was studied. The coupling method had more advantages than powder sintering method and sol-gel method.